Medical devices are used to deliver neurostimulation therapy to patients to treat a variety of symptoms or conditions such as chronic pain, tremor, Parkinson's disease, epilepsy, incontinence, or gastroparesis. Typically, medical devices deliver neurostimulation therapy in the form of electrical pulses via leads that include electrodes. To treat the above-identified symptoms or conditions, for example, the electrodes may be located proximate to the spinal cord, peripheral nerves, pelvic nerves, or stomach, or within the brain of a patient. The electrodes carried on one or more leads that are implanted within a patient may be referred to as an electrode set or array.
A clinician may select values for a number of programmable parameters in order to define the neurostimulation therapy to be delivered to a patient. For example, the clinician may select an amplitude, which may be a current or voltage amplitude, and pulse width for a stimulation waveform to be delivered to the patient, as well as a rate at which the pulses are to be delivered to the patient. The clinician may also select as parameters particular electrodes within an electrode set to be used to deliver the pulses, e.g., a combination of electrodes from the electrode set. A combination of electrodes may be defined by the polarities, e.g., positive, negative, or off (high impedance), of each of the electrodes within the electrode set. A group of parameter values may be referred to as a program in the sense that they drive the neurostimulation therapy to be delivered to the patient.
In some cases, a medical device delivers neurostimulation therapy according to a group of two ore more programs, i.e., a program group. The medical device may alternate delivery of neurostimulation therapy pulses according to the various programs of a program group at a rate such that the patient does not perceive transitions between the programs. For example, the medical device may deliver each neurostimulation therapy pulse according to a different one of the plurality of programs of a program group, or may deliver a plurality of pulses according to one of the programs before switching to another of the programs of the program group. The constituent programs of a program group may address different symptoms, allowing the program group as a whole to more completely address the symptoms of a patient. For example, the constituent programs of a program group may address different regions of pain, allowing the group as whole to address a complex pain pattern.
The process of selecting values for the parameters that provide adequate therapeutic results can be time consuming, and may require a great deal of trial and error before one or more preferred programs are discovered. The preferred programs may be programs that are better in terms of clinical efficacy versus side effects experienced and power consumption than other programs tested. Where a medical device delivers neurostimulation therapy according to program groups, the process of manually assembling preferred programs into groups may further increase the amount of time and effort required for a therapy programming session. For example, manual assembly of programs into groups may require a clinician to recall from memory or handwritten notes the efficacy of a plurality of programs, as well as, for example, the locations at which the patient experiences pain, and at which the patient experienced the paresthesia produced by the various programs.